Navigating Global Patent Filing: The Role of the PCT in 1970

Before the Patent Cooperation Treaty (PCT) came into existence, an inventor wanting to protect their invention in, say, ten countries had to file ten separate patent applications – each in a different language, each with separate fees, and each subject to different national procedures. For startups, individual inventors, and even large companies, this was a logistical and financial nightmare. The PCT, concluded on 19 June 1970 at the Washington Diplomatic Conference, fundamentally changed that. It created a single, unified filing pathway that opened the door to international patent protection without the immediate burden of country-by-country applications.

What is the PCT and who administers it? 🔗

The Patent Cooperation Treaty (PCT) is an international patent law treaty administered by the World Intellectual Property Organization (WIPO), based in Geneva, Switzerland. It provides a standardised procedure through which inventors can file a single “international application” and simultaneously seek patent protection across all PCT contracting states. As of early 2025, the treaty has 158 contracting states, making it one of the most widely adopted IP treaties in the world.

The treaty entered into force on 24 January 1978, with just 18 member states. The first international applications were filed on 1 June 1978. Since then, it has been amended in 1979 and modified in 1984 and 2001. By 2020, the cumulative number of PCT applications filed since the system became operational was expected to reach 4 million – a measure of how central the PCT has become to global innovation strategy.

Any state that is a party to the Paris Convention for the Protection of Industrial Property is eligible to join the PCT. Contracting states collectively form the International Patent Cooperation Union, which has an Assembly that oversees regulatory amendments and the PCT’s budget.

The core idea: one application, many countries 🔗

The fundamental value of the PCT is straightforward. Instead of filing separate national patent applications in every country where protection is sought, an inventor files one international application in one language and pays one set of fees. That single application has the same legal effect as filing directly in each of the designated contracting states on the same date.

This is not a “global patent” – no such thing exists. Patent protection remains territorial, and each national or regional patent office ultimately decides whether to grant the patent under its own laws. What the PCT does is simplify and delay the most expensive parts of the process, giving inventors more time and information before they commit resources to individual countries.

The PCT process: two phases explained 🔗

The PCT procedure operates in two clearly defined stages – the international phase and the national phase.

International phase 🔗

The international phase begins when the applicant files the PCT application with a Receiving Office (RO) – typically their national patent office or directly with the International Bureau of WIPO. The application must comply with PCT formality requirements and be filed in one of the permitted languages, which currently include English, French, German, Japanese, Russian, Spanish, Chinese, and Arabic.

Once filed, an International Searching Authority (ISA) – one of the world’s major patent offices, such as the European Patent Office (EPO), the Japan Patent Office (JPO), or the Korean Intellectual Property Office (KIPO) – conducts a comprehensive prior art search. This produces an International Search Report (ISR), which lists published documents that could affect the patentability of the invention, along with a written opinion on whether the invention appears novel, inventive, and industrially applicable.

The ISR must be established within three months of the ISA receiving the search copy, or within nine months from the priority date, whichever is later. The application is then published by WIPO 18 months from the priority date, making the invention and the ISR publicly available. This transparency also benefits third parties, who can better assess the patentability landscape for the disclosed invention.

Optional international preliminary examination 🔗

After the ISR is issued, the applicant has the option to request an International Preliminary Examination – what is referred to as Chapter II of the PCT. This is conducted by an International Preliminary Examining Authority (IPEA) and results in an International Preliminary Examination Report (IPER), formally titled the International Preliminary Report on Patentability (Chapter II).

The IPER provides a non-binding, preliminary opinion on whether the invention is novel, involves an inventive step, and is industrially applicable. While it does not guarantee a patent, it gives the applicant a stronger basis for evaluating the chances of success in each target country before committing to national-phase costs. Requesting Chapter II examination requires payment of a handling fee to the International Bureau and a preliminary examination fee to the IPEA.

National phase 🔗

The national phase begins, in most cases, 30 months from the priority date – though some countries, including India, allow up to 31 months. At this point, the applicant must approach each country’s national or regional patent office individually, submit any required translations, pay national filing fees, and comply with local requirements. Each office then independently evaluates the application and decides whether to grant the patent.

The value of this delayed national phase cannot be overstated. An inventor gets approximately two and a half years from their initial filing to assess market potential, secure funding, and decide strategically which countries are commercially worth pursuing – all while holding an internationally recognised filing date.

PCT filing in India: what applicants need to know 🔗

India is a contracting state to the PCT, and the Indian Patent Office (IPO) functions as both a Receiving Office (for international phase applications filed from India) and a Designated Office (for national phase entries into India).

An Indian inventor can file a PCT application claiming priority from an earlier Indian application, within 12 months of that Indian filing. The PCT application can be filed directly with the International Bureau of WIPO or through the Indian Patent Office as the Receiving Office.

For national phase entry in India, applicants have 31 months from the earliest priority date to enter the Indian national phase. Key documents required include Form 1 (application for grant of patent), the complete specification in Form 2, a power of attorney in Form 26, and a verified English translation if the PCT application was not filed or published in English. Importantly, the Indian Patent Office does not permit amendments to the application at the time of national phase entry – a notable distinction from many other jurisdictions.

Following the Patents (Amendment) Rules, 2024, the Request for Examination (Form 18) must now be filed within the same 31-month statutory window as the national phase entry itself, for applications filed on or after 15 March 2024. Missing this deadline can result in the application being treated as abandoned. The term of a patent granted through the PCT national phase in India is 20 years from the international filing date accorded under the PCT.

Key benefits of the PCT system 🔗

The PCT offers concrete advantages that make it the preferred route for most international patent strategies. First, cost deferral: the bulk of national-phase costs – translations, attorney fees, national filing fees – are deferred until the 30/31-month mark, giving applicants time to assess whether pursuing protection in each country is commercially worthwhile.

Second, a single filing date: the PCT filing date is treated as the actual filing date in every designated state. This unified date protects the inventor’s priority position globally without requiring simultaneous filings in every target country.

Third, informed decision-making: the ISR and written opinion give applicants early feedback on their invention’s patentability, reducing the risk of spending heavily on national phase entries in countries where the patent is unlikely to be granted. As WIPO notes, a favourable international search report can make national phase examination easier for patent offices, sometimes resulting in faster grants.

Fourth, flexibility: applicants can choose which countries to pursue during the national phase based on updated market intelligence, business priorities, and the ISR findings. They are not locked into decisions made at the time of filing.

What the PCT does not do 🔗

It is a common misconception that a PCT application results in a “world patent.” It does not. A PCT application establishes a filing date but does not directly result in a granted patent. The decision to grant a patent rests exclusively with each national or regional patent office, applying its own laws and standards. Additionally, costs during the national phase – especially translation costs for multiple countries – can still be substantial. The PCT simplifies and streamlines the international filing process; it does not eliminate the eventual burden of national compliance.

PCT vs. Paris Convention route: a quick comparison 🔗

Inventors seeking international protection can also use the Paris Convention route, which requires filing individual national applications within 12 months of the first filing. The PCT, by contrast, extends this window to 30 or 31 months and consolidates the search and preliminary examination steps. The PCT is generally considered more cost-effective and strategically flexible for those pursuing protection in multiple countries, particularly when the inventor needs time to validate the market before committing to expensive national filings.

The Paris Convention remains useful for inventors targeting a small number of countries quickly, where the simpler direct filing process is sufficient. For inventors with broader international ambitions – and especially startups and SMEs managing cash flow – the PCT’s deferred cost structure and extended timelines are a clear advantage.

What do you think? Given that the PCT does not grant a patent but only facilitates the filing process, do you think it places too much power in the hands of individual national patent offices – or is this territorial approach the right balance between international coordination and national sovereignty? And for Indian inventors with limited resources, does a 31-month window to assess commercial viability before committing to national phase filings genuinely level the playing field, or are the associated costs still prohibitive?

References

1. https://www.wipo.int/en/web/pct-system/treaty/about
2. https://www.wipo.int/pct/en/faqs/faqs.html
3. https://en.wikipedia.org/wiki/Patent_Cooperation_Treaty
4. https://ipindia.gov.in/writereaddata/portal/images/pdf/final_frequently_asked_questions_-patent.pdf
5. https://boldip.com/blog/global-patents-understanding-the-pct-patent-cooperation-treaty/
6. https://www.intepat.com/blog/pct-patent-india
7. https://www.aipla.org/list/innovate-articles/entering-the-national-phase-of-patent-applications-in-india-under-the-patent-cooperation-treaty
8. https://www.etblaw.com/what-is-a-patent-cooperation-treaty-application/
9. https://aggarwalassociates.com/patent/what-is-patent-cooperation-treaty-pct/